1. Field of the Invention
The present invention relates generally to electromagnetic relays, more particularly, to a latching magnetic relay assembly with two electrically separated excitation coils capable of handling current transfers of up to and greater than 200 amps.
2. Description of the Prior Art
There are a few designs for latching magnetic relay assemblies currently in the prior art. These latching magnetic relay assemblies typically include a relay motor assembly that is magnetically coupled to an actuation assembly. The actuation assembly is then operatively coupled to a contact spring that is positioned opposite a pair of conductively isolated contact points. The relay motor typically drives the actuation assembly which in turn drives the contact spring into contact with a pair of contact points positioned directly across from it.
The conductive springs typically serve a dual purpose. They ensure good contact with the contact points, and they form a conductive pathway between the contact points. Conductive springs are typically made of copper or a copper alloy, the copper alloys typically have lower conductivity than plain copper. Plain copper can typically sustain less than 20 amps per square millimeter without causing excess heat build up in the copper. Excess heat build up in the conductive springs will cause the conductive spring to lose their spring property. This results in a loss of contact pressure, which leads to increased contact resistance which in turn causes the relay to fail. Consequently, most latching magnetic relays can only sustain currents of less than 20 amps per square millimeter through their copper conductive springs.
In order to increase current density while minimizing the heat generated by higher currents only two options are currently available. One is to make the conductive spring wider, requiring an increase in the size of the relay and increasing the bending force needed by the actuator assembly and the relay motor. The other option to increase the thickness of the spring which will also increase the bending force needed by the actuator assembly and the relay motor. Consequently, typical latching magnetic relays are not particularly suited for applications which require higher current flows of up to 100 amps.
U.S. Pat. No. 4,092,620 issued to Schuessler et al. discloses an electrical connection for the moving contacts of a relay. This invention provides an improved electrical connection for the moving contacts of a relay which simplifies the assembly operation. Specifically, this invention provides an electrical connection between a contact pin in the header of a relay and the pivoting blades supporting the moving contacts of the relay switch. The electrical connection is in the form of a cantilever spring contact having one end attached permanently to a contact pin by a supporting bracket, the cantilevered spring extending substantially parallel to the blade supporting the moving contacts of the switch. The free end of the cantilever spring is formed with a curved projecting portion which is urged by the spring against the surface of the contact blade adjacent the pivotal axis of the blade.
U.S. Pat. No. 4,101,855 issued to Drapeau discloses a miniature relay. This invention provides a miniature relay comprising an electromagnet assembly including a coil carried by a magnetic frame, the electromagnet being fixed to a supporting member of non-magnetic material which, in turn, is fixed to a header containing an assembly of stationary and movable contact members electrically coupled to terminal pins extending through the header. The magnetic frame includes a core portion extending longitudinally through and beyond the coil and terminating in an end facing the header, and the frame also includes a pole piece portion operatively associated with the coil. An armature is held in position by cooperation between a pair of spaced-apart holding elements extending from the electromagnet assembly and a portion of the armature shaped and dimensioned to fit in the region between the holding elements. The spaced-apart holding elements provide a saddle for the armature portion, and the armature is continuously urged into that saddle by biasing means carried by the header. The pull in force of the electromagnet can be enhanced by a mating tab and notch configuration in cooperating portions of the armature and pole piece or by a pole piece end portion disposed to present increased surface area to the armature.
U.S. Pat. No. 4,795,994 issued to Hoffmann discloses an electromechanical DC-RF relay. This invention includes a structure for an electromagnetic relay that provides high reliability and resistance to environmental extremes of shock, acceleration, vibration, temperature, and humidity, while providing a fast acting relay action in a configuration suitable for signal frequencies from DC to about 8 GHz. This invention includes a slider comprising a permanent magnet embedded in a non-conductive material slotted to loosely receive a mid-portion of at least one contact reed. One end of the contact reed is pivotally connected to an input pin of the relay, such that the contact reed can pivot from a first position to a second position while remaining in electrical contact with the input pin. The slider is situated such that the other end of the contact reed is normally in electrical contact with a first output pin, held there by magnetic attraction of the permanent magnet to the relay electromagnet. When the electromagnet of the relay is activated, the slider is repelled from the electromagnet, causing the contact reed to be pivoted away from the first contact pin until it stops in electrical contact against a second output pin. The contact reed slides within the slot of the slider as the contact reed pivots. No hard-stop adjustment or other adjustment is needed.
U.S. Pat. No. 5,546,061 issued to Okabayashi et al. discloses a plunger type electromagnetic relay with arc extinguishing structure. According to one aspect of this invention, there is provided an electromagnetic relay which comprises a movable contact retainer having disposed thereon a pair of movable contacts, a stationary contact retainer having disposed thereon a pair of stationary contacts at a given interval away from the movable contacts, a magnetically driving means for selectively driving the stationary contact retainer to bring the stationary contacts into engagement with and disengagement from the movable contacts, and a pair of permanent magnets having magnetic poles oriented opposite each other across the pair of the movable contacts retained on the movable contact retainer. According to another aspect of this invention, there is provided an electromagnetic relay which comprises a movable contact retainer having disposed thereon a pair of movable contacts, a stationary contact retainer having disposed thereon a pair of stationary contacts at a given interval away from the movable contacts, a magnetically driving means for selectively driving the stationary contact retainer to bring the stationary contacts into engagement with and disengagement from the movable contacts, and a pair of permanent magnets having magnetic poles oriented, in alignment with a current flow through the movable contact retainer, diametrically opposite each other across the pair of the movable contacts retained on the movable contact retainer.
U.S. Pat. No. 5,880,655 issued to Dittmann et al. discloses an electromagnetic relay. The relay of this invention includes a coil assembly enclosed in a top enclosure made from insulating material. The coil assembly includes a spooled coil body, a core, pole shoes and winding terminal elements assembly and is disposed above a pivoting armature which is connected to contact springs via a carrier element of insulating material. The relay of this invention also includes a base made from insulating material and which contains terminal paths for stationary cooperating contact elements as well as contact terminal elements. The armature is disposed above the base via bearing supports and bearing bands integrated in the contact springs. A frame is disposed over the base and forms a housing for the relay together with the base and with the top enclosure. The housing encapsulates the contact space of the relay, wherein the frame with the base represents the lower housing part and the top enclosure for the coil assembly represents the upper housing part.
In order to accomplish the goal of transferring currents of up to 100 amps for use in regulating the transfer of electricity or in other applications requiring the switching of current of up to 100 amps, a latching magnetic relay assembly with a linear motor is invented. U.S. Pat. No. 6,046,660 issued to Gruner disclosed a latching magnetic relay assembly with a linear motor. This invention is a latching magnetic relay capable of transferring currents of greater than 100 amps for use in regulating the transfer of electricity or in other applications requiring the switching of currents of greater than 100 amps. A relay motor assembly has an elongated coil bobbin with an axially extending cavity therein. An excitation coil is wound around the bobbin. A generally U shaped ferromagnetic frame has a core section disposed in and extending through the axially extending cavity in the elongated coil bobbin. Two contact sections extend generally perpendicularly to the core section and rises above the motor assembly. An actuator assembly is magnetically coupled to the relay motor assembly. The actuator assembly is comprised of an actuator frame operatively coupled to a first and a second generally U-shaped ferromagnetic pole pieces, and a permanent magnet. A contact bridge made of a sheet of conductive material copper is operatively coupled to the actuator assembly. However, there has never been disclosed a latching magnetic relay with two electrically separated excitation coils capable of handling currents of up to 200 amps.
Accordingly, there is a need for a latching magnetic relay, which is capable of handling currents of up to 200 amps.
Accordingly, there is a need for a latching magnetic relay, which is capable of performing the function of two latching magnetic relays.
The present invention is a latching magnetic relay assembly with two electrically insulated excitation coil capable of transferring currents of up to 200 amps for use in regulating the transfer of electricity or in other applications requiring the switching of currents of up to 200 amps.
A latching magnetic relay assembly in present invention comprises a relay motor with a first coil bobbin having a first excitation coil wound therearound and a second coil bobbin having a second excitation coil wound therearound, an actuator assembly magnetically coupled to the relay motor, the actuator assembly having a first end and a second end, a first means for conductive contact, the first means for conductive contact operatively coupled to the first end of the actuator assembly, the movement of the actuator assembly either driving the first means for conductive contact into contact with a first pair of contact points positioned directly opposite the first means for conductive contact, the first means for conductive contact acting as a first conductive pathway between the first pair of contact points, or driving the first means for conductive contact into breaking contact with the first pair of contact points, each of the first pair of contact points connecting to a first blow-out magnet, the movement of the actuator assembly initiated by the relay motor assembly, and a second means for conductive contact, the second means for conductive contact operatively coupled to the second end of the actuator assembly, the movement of the actuator assembly either driving the second means for conductive contact into contact with a second pair of contact points positioned directly opposite the second means for conductive contact, the second means for conductive contact acting as a second conductive pathway between the second pair of contact points, or driving the second means for conductive contact into breaking contact with the second pair of contact points, each of the second pair of contact points connecting to a second blow-out magnet, the movement of the actuator assembly initiated by the relay motor assembly.
The latching magnetic relay in present invention further comprises a housing having a top cover and a bottom cover with a plurality of top contact terminal assemblies and a plurality of bottom contact terminal assemblies attached thereto and extending through walls of the housing, the relay motor, the actuator assembly, the first means for conductive contact, and the second means for conductive contact being disposed within the housing, the top contact terminal assembly having the first pair of contact points positioned across the first means for conductive contact, a first gap of at least 1.6 mm separating the first means for conductive contact and each of the first pair of contact points, the bottom contact terminal assembly having the second pair of contact points positioned across the second means for conductive contact, a second gap of at least 1.6 mm separating the second means for conductive contact and each of the second pair of contact points.
Both the first means for conductive contact and the second means for conductive contact are made of copper and have a width of 10 millimeters and a thickness of 1 millimeter. A plurality of first means for conductive contact are operatively coupled to the first end of the actuator assembly, and a plurality of second means for conductive contact are operatively coupled to the second end of the actuator assembly. A plurality of first pairs of contact buttons are conductively connected to the first means for conductive contact. A plurality of second pairs of contact buttons are conductively connected to the second means for conductive contact.
In a preferred embodiment of the present invention, the first means for conductive contact is in breaking contact with the first pair of contact points when the second means for conductive contact is into contact with the second pair of contact points, and the second means for conductive contact is in breaking contact with the second pair of contact points when the first means for conductive contact is into contact with the first pair of contact points.
In a second embodiment of the present invention, the first means for conductive contact is in breaking contact with the first pair of contact points when the second means for conductive contact is in breaking contact with the second pair of contact points, and the second means for conductive contact is into contact with the second pair of contact points when the first means for conductive contact is into contact with the first pair of contact points.
In a third embodiment of the present invention, a latching magnetic relay assembly comprises a relay motor with a first coil bobbin having a first excitation coil wound therearound and a second coil bobbin having a second excitation coil wound therearound, an actuator assembly magnetically coupled to the relay motor, the actuator assembly having a first end and a second end, and a means for conductive contact, the means for conductive contact operatively coupled to the first end of the actuator assembly, the movement of the actuator assembly either driving the means for conductive contact into contact with a pair of contact points positioned directly opposite the means for conductive contact, the means for conductive contact acting as a conductive pathway between the pair of contact points, or driving the means for conductive contact into breaking contact with the pair of contact points, each of the pair of contact points connecting to a blow-out magnet, the movement of the actuator assembly initiated by the relay motor assembly.